[PATCH V2] staging: dgap: implement proper error handling in dgap_firmware_load()

Daeseok Youn
2014-05-27T07:10:22Z

When dgap_tty_init() and dgap_tty_register_ports() are failed,
these are needed to free some memory properly.

It can be handled by calling dgap_tty_uninit() and dgap_cleanup_board().
But tty's ports are not registered yet when these function are failed,
so it need to switch with boolean value whether tty's ports are
registered.

Signed-off-by: Daeseok Youn <daeseok.youn@gmail.com>
---
V2: remove "brd->nasync = 0" for avoiding to call some destroyer
for unregistering tty's ports.

I'm not sure about add a parameter in dgap_tty_uninit() for checking
whether tty's ports are registered.
please review this. And if I am wrong, let me know.

drivers/staging/dgap/dgap.c | 34 +++++++++++++++++++++++-----------
1 files changed, 23 insertions(+), 11 deletions(-)

diff --git a/drivers/staging/dgap/dgap.c b/drivers/staging/dgap/dgap.c
index 65d651e..03a3a4b 100644
--- a/drivers/staging/dgap/dgap.c
+++ b/drivers/staging/dgap/dgap.c
@@ -124,7 +124,7 @@ static void dgap_tty_send_xchar(struct tty_struct *tty, char ch);

static int dgap_tty_register(struct board_t *brd);
static int dgap_tty_init(struct board_t *);
-static void dgap_tty_uninit(struct board_t *);
+static void dgap_tty_uninit(struct board_t *, bool);
static void dgap_carrier(struct channel_t *ch);
static void dgap_input(struct channel_t *ch);

@@ -620,7 +620,7 @@ static void dgap_cleanup_module(void)

for (i = 0; i < dgap_numboards; ++i) {
dgap_remove_ports_sysfiles(dgap_board[i]);
- dgap_tty_uninit(dgap_board[i]);
+ dgap_tty_uninit(dgap_board[i], true);
dgap_cleanup_board(dgap_board[i]);
}

@@ -954,19 +954,23 @@ static int dgap_firmware_load(struct pci_dev *pdev, int card_type)
* Do tty device initialization.
*/
ret = dgap_tty_init(brd);
- if (ret < 0) {
- dgap_tty_uninit(brd);
- return ret;
- }
+ if (ret < 0)
+ goto err_cleanup;

ret = dgap_tty_register_ports(brd);
if (ret)
- return ret;
+ goto err_cleanup;

brd->state = BOARD_READY;
brd->dpastatus = BD_RUNNING;

return 0;
+
+err_cleanup:
+ dgap_tty_uninit(brd, false);
+ dgap_cleanup_board(brd);
+ return ret;
+
}

/*
@@ -1488,19 +1492,20 @@ static int dgap_tty_init(struct board_t *brd)
* Uninitialize the TTY portion of this driver. Free all memory and
* resources.
*/
-static void dgap_tty_uninit(struct board_t *brd)
+static void dgap_tty_uninit(struct board_t *brd, bool ports_registered)
{
struct device *dev;
- int i;
+ int i = 0;

if (brd->dgap_major_serial_registered) {
dgap_boards_by_major[brd->serial_driver->major] = NULL;
brd->dgap_serial_major = 0;
- for (i = 0; i < brd->nasync; i++) {
+ while (ports_registered && i < brd->nasync) {
tty_port_destroy(&brd->serial_ports[i]);
dev = brd->channels[i]->ch_tun.un_sysfs;
dgap_remove_tty_sysfs(dev);
tty_unregister_device(brd->serial_driver, i);
+ i++;
}
tty_unregister_driver(brd->serial_driver);
put_tty_driver(brd->serial_driver);
@@ -1508,14 +1513,21 @@ static void dgap_tty_uninit(struct board_t *brd)
brd->dgap_major_serial_registered = FALSE;
}

+ /*
+ * Clear index of tty's port for unregistering
+ * ports of printer driver
+ */
+ i = 0;
+
if (brd->dgap_major_transparent_print_registered) {
dgap_boards_by_major[brd->print_driver->major] = NULL;
brd->dgap_transparent_print_major = 0;
- for (i = 0; i < brd->nasync; i++) {
+ while (ports_registered && i < brd->nasync) {
tty_port_destroy(&brd->printer_ports[i]);
dev = brd->channels[i]->ch_pun.un_sysfs;
dgap_remove_tty_sysfs(dev);
tty_unregister_device(brd->print_driver, i);
+ i++;
}
tty_unregister_driver(brd->print_driver);
put_tty_driver(brd->print_driver);
--
1.7.1